ALDOL CONDENSATION OF TRIFLUOROACETOPHENONE AND ACETONE - TESTING A PREDICTION

Rate and equilibrium constants have been determined for both stages of the aldol condensation of acetone with trifluoroacetophenone. The ext ensive hydration of trifluoroacetophenone and the acid dissociation of the hydrate complicated the kinetic analysis. Dehydration of the inte rmediate ketol leads to two enones which equilibrate in base more rapi dly than they undergo hydration to the ketol. This is consistent with interconversion via the enolate of the ketol, which loses OH- faster t han it undergoes C-protonation. The rate constant determined for the a ldol addition step is in satisfactory agreement with the value predict ed from a Marcus correlation.